ChangeSpec

changespec.orgLaunched Apr 2026

Open JSON format for API breaking changes, deprecations, and supply-chain retractions.

Dev Toolsapijson-formatbreaking-changesdeprecationsupply-chainopen-standarddeveloper-tooling
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/ About /

ChangeSpec is an open JSON event format (Apache 2.0) that standardizes how API vendors communicate breaking changes, deprecations, CVE advisories, and package retractions. It provides a single structured event schema that IDEs, CI pipelines, AI assistants, and compliance tools can consume automatically. Reference implementations are available in Go, TypeScript, and Python.

/ How it works /

Vendors publish a single structured ChangeSpec JSON event per change, and any tool that supports the format automatically delivers it to developers through their preferred channel.

/ Who it's for /

Developers consuming external APIs, API/SDK vendors, and security engineers

/ More info /

Background.

Status
launched
Business model
open-source
Launched
Apr 2026

Contact

/ Discovered patterns /

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